Table 1

A comparison of the published series of patients with PsA

Feature	Roberts et al (1976)¹⁴	Kammer et al (1979)¹⁵	Scarpa et al (1984)¹⁶	Gladman et al (1987)¹⁷	Helliwell et al (1991)¹⁸	Torre-Alonso et al (1991)¹⁹	Veale et al (1994)²⁰	Jones et al (1994)²¹	Trabace et al (1994)²²	Marsal et al (1999)²³
No of patients	168	100	62	220	50	180	100	100	58	73
Male/female	67/101	47/53	29/33	104/116	32/18	99/81	59/41	43/57	35/33	37/36
Age of onset (years)	36–45	33–45	40–60	37	39	39	34	37.6	42	42
Oligoarthritis (%)	53	54	16	14	14	37	43	26	50	7
Polyarthritis (%)	54	25	39	40	78	35	33	63	40	88
Distal (%)	17	?	7.5	12	0	0	16	1	?	4
Back (%)	5	21	21	2	6	7	4	6	?	1
Mutilans (%)	5	?	2.3	16	2	4	2	4	?	14
Sacroiliitis (%)	?	?	16	27	36	20	15	6	43	14
Joints before skin (%)	16	30	?	17	?	15	?	18	?	?